.\"	$OpenBSD: dz.4,v 1.13 2013/06/02 20:42:27 tedu Exp $
.\"	$NetBSD: dz.4,v 1.3 1996/03/03 17:13:29 thorpej Exp $
.\"
.\" Copyright (c) 1980, 1991 Regents of the University of California.
.\" All rights reserved.
.\"
.\" Redistribution and use in source and binary forms, with or without
.\" modification, are permitted provided that the following conditions
.\" are met:
.\" 1. Redistributions of source code must retain the above copyright
.\"    notice, this list of conditions and the following disclaimer.
.\" 2. Redistributions in binary form must reproduce the above copyright
.\"    notice, this list of conditions and the following disclaimer in the
.\"    documentation and/or other materials provided with the distribution.
.\" 3. Neither the name of the University nor the names of its contributors
.\"    may be used to endorse or promote products derived from this software
.\"    without specific prior written permission.
.\"
.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
.\" ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
.\" SUCH DAMAGE.
.\"
.\"     from: @(#)dz.4	6.3 (Berkeley) 3/27/91
.\"
.Dd $Mdocdate: June 2 2013 $
.Dt DZ 4 vax
.Os
.Sh NAME
.Nm dz
.Nd
.Tn DZ-11
multiplexer device interface
.Sh SYNOPSIS
.Cd "dz0 at uba0 csr 0160100"
.Cd "dz0 at vsbus0 csr 0x200a0000" Pq "DC-367"
.Cd "dz0 at vsbus0 csr 0x25000000" Pq "VS4000/90 4000/10x MV3100/9x"
.Cd "dz* at fwio?                " Pq "VAXstation 35x0 and 38x0"
.Cd "lkkbd0 at dz0 line 0"
.Cd "lkms0  at dz0 line 1"
.Sh DESCRIPTION
A
.Tn DZ-11
provides 4 or 8 communication lines with partial modem control,
adequate for
.Ox
dialup use.
.\" .Pp
.\" An optional argument
.\" .Ar flags
.\" may be supplied with the device specification
.\" in the config file indicating
.\" that the line corresponding to
.\" bit number
.\" .Ar i
.\" is not properly
.\" connected, and should be treated as hard-wired with carrier
.\" always present.
.\" Thus specifying
.\" .Ql flags 0x04
.\" for
.\" .Li dz0
.\" would cause line
.\" .Pa tty02
.\" to be treated in this way.
.Pp
Normal I/O
control parameters for individual lines are managed by
.Xr ioctl 2
calls.
Line speeds may be initiated via
the
.Xr ttys 5
file or
.Xr stty 1 ,
see
.Xr tty 4 .
.Pp
The
.Nm dz
driver monitors the rate of input on each board,
and switches between the use of character-at-a-time interrupts
and input silos.
While the silo is enabled during periods of high-speed input,
the driver polls for input 30 times per second.
.Pp
On VAXstation systems, lines 0 and 1 are tied to the keyboard and mouse
connectors, which are driven by the
.Nm lkkbd
and
.Nm lkms
drivers, respectively.
.Sh FILES
.Bl -tag -width /dev/tty0[0-7] -compact
.It Pa /dev/tty0[0-7]
dialups
.El
.Sh DIAGNOSTICS
.Bl -diag
.It dz0: silo overflow.
The 64 character input silo overflowed
before it could be serviced.
This can happen if a hard error occurs when the
.Tn CPU
is running with elevated priority, as the system will
then print a message on the console with interrupts disabled.
It is not serious.
.El
.Sh SEE ALSO
.Xr intro 4 ,
.Xr lkkbd 4 ,
.Xr lkms 4 ,
.Xr tty 4 ,
.Xr uba 4 ,
.Xr vsbus 4
.Sh HISTORY
A
.Nm
driver appeared in
.At 32v .
